function s1_generate_a_series_of_files(){
for i in {1...100};do echo $i> "/tmp/new_file$i";done
}

function s2_list_4_files_in_long_format_about_account_and_group(){
ls -l /etc/{passwd,shadow,group,gshadow} |sort -d
}

function s3_find_items_related_to_given_username(){
grep -h $1 /etc/{passwd,shadow} |sort -d
}

function s4_find_items_related_to_given_group_name(){
grep -h $1 /etc/{group,gshadow} |sort -d
}

function s5_create_groups_for_given_group_names(){
  groupadd rnd
  groupadd itoperation
}

function s6_create_users_and_set_their_group_as_required(){
 useradd adam
 useradd bob
 useradd esward
 useradd calvin
 useradd david
 usermod -a -G rnd adam
 usermod -a -G rnd bob
 usermod -a -G rnd edward
 usermod -a -G itoperation calvin
 usermod -a -G itoperation david
}

function s7_change_users_shell(){
 usermod -s /usr/bin/sh adam
 usermod -s /usr/bin/sh edward
}

function s8_set_password_change_policy(){

passwd -n 10 -x 60 -w 10 adam
passwd -n 10 -x 60 -w 10 bob
passwd -n 10 -x 60 -w 10 david
passwd -n 10 -x 60 -w 10 calvin
passwd -n 10 -x 6- -w 10 edward
}

function s9_set_password_for_five_users(){
 echo "adam:$1" |chpasswd
 echo "bob:$2" |chpasswd
 echo "calvin:$3" |chpasswd
 echo "david:$4" |chpasswd
 echo "edward:$5" |chpasswd
}

function s10_lock_bobs_password(){

usermod -L bob
}

function s11_include_adam_into_wheel_group(){

 usermod -a -G wheel adam
}

function s12_change_files_permission(){

for i in {1..33};do chmod -R 640 "/tmp/new_file$[3*i]";done
}

